Class Box`Abstract`

Box

Hierarchy (View Summary)

Box
- CanvasBox

Constructors

constructor

new Box(parent: undefined | Box, id: string): Box
Constructor.

If parent is provided, parent.onChildAdded(this) is called.
Parameters
- parent: undefined | Box
  parent box
- id: string
  id of this box
Returns Box

Properties

`Protected`_layoutPosition

_layoutPosition: undefined | Geometry.Point

`Protected`_measuredSize

_measuredSize: undefined | Geometry.Rect

`Protected`_needsDrawing

_needsDrawing: boolean = true

`Protected`_needsLayoutX

_needsLayoutX: boolean = true

`Protected`_needsMeasuring

_needsMeasuring: boolean = true

`Protected` `Readonly`_parent

_parent: undefined | Box

`Protected`_ready

_ready: boolean = true

canvasRegion

canvasRegion: Geometry.RectPositioned = RectsPlaceholderPositioned

Rectangle Box occupies in canvas/etc

`Protected`children

children: Box[] = []

debugHue

debugHue: number = ...

debugLayout

debugLayout: boolean = false

`Readonly`id

id: string

takesSpaceWhenInvisible

takesSpaceWhenInvisible: boolean = false

Accessors

desiredRegion

get desiredRegion(): undefined | BoxRect
Gets the box's desired region, or undefined

Returns undefined | BoxRect
set desiredRegion(v: undefined | BoxRect): void
Sets the box's desired region. Calls onLayoutNeeded()
Parameters
- v: undefined | BoxRect
Returns void

root

get root(): Box
Returns the root box

Returns Box

visible

get visible(): boolean
Gets visible state

Returns boolean
set visible(v: boolean): void
Sets visible state
Parameters
- v: boolean
Returns void

Methods

debugLog

debugLog(m: any): void
Debug log from this box context
Parameters
- m: any
Returns void

drawingInvalidated

drawingInvalidated(_reason: string): void
Parameters
- _reason: string
Returns void

getChildren

getChildren(): Generator<never, ArrayIterator<[number, Box]>, unknown>
Returns Generator<never, ArrayIterator<[number, Box]>, unknown>

hasChild

hasChild(box: Box): boolean
Returns true if box is a child
Parameters
- box: Box
Returns boolean

`Protected`layoutApply

layoutApply(l: Layout): boolean
Parameters
- l: Layout
Returns boolean

layoutInvalidated

layoutInvalidated(reason: string): void
Calls notifyChildLayoutNeeded
Parameters
- reason: string
Returns void

`Protected`layoutSelf

layoutSelf(
    measureState: MeasureState,
    layoutState: LayoutState,
    _parent?: Layout,
): undefined | Geometry.Point
Parameters
- measureState: MeasureState
- layoutState: LayoutState
- Optional_parent: Layout
Returns undefined | Geometry.Point

layoutStart

layoutStart(
    measureState: MeasureState,
    layoutState: LayoutState,
    force: boolean,
    parent?: Layout,
): undefined | Layout
Parameters
- measureState: MeasureState
- layoutState: LayoutState
- force: boolean
- Optionalparent: Layout
Returns undefined | Layout

`Protected`measureApply

measureApply(m: Measurement): boolean
Applies actual size, returning true if size is different than before
1. Sets _needsLayout to false.
2. Sets visual to m
3. Calls measureApply on each child
4. If there's a change or force, sets needsDrawing to true, and notifies root of measureApplied
Parameters
- m: Measurement
  Measurement for box
Returns boolean

`Protected`measurePreflight

measurePreflight(): void
Prepare for measuring

Returns void

`Protected`measureSelf

measureSelf(opts: MeasureState, parent?: Measurement): string | Geometry.Rect
Measure the box
1. Uses desired rectangle, if possible
2. Otherwise uses parent's size
Parameters
- opts: MeasureState
  Measure state
- Optionalparent: Measurement
  Parent size
Returns string | Geometry.Rect

measureStart

measureStart(
    opts: MeasureState,
    force: boolean,
    parent?: Measurement,
): undefined | Measurement
Start of measuring
1. Keeps track of measurements in opts.measurements
2. If this box takes space 2.1. Measure itself if needed 2.2. Use size
3. Calls measureStart on each child
Parameters
- opts: MeasureState
  Options
- force: boolean
  Force measurement
- Optionalparent: Measurement
  Parent's measurement
Returns undefined | Measurement
Measurement

notify

notify(message: string, source: Box): void
Sends a message to all child boxes.

This first calls onNotify on this instance, before calling notify() on each child.
Parameters
- message: string
- source: Box
Returns void

`Protected`onChildAdded

onChildAdded(child: Box): void
Notification a child box has been added

Throws if
- child has parent as its own child
- child is same as this
- child is already child of this
Parameters
- child: Box
Returns void

`Protected`onNotify

onNotify(_message: string, _source: Box): void
Handles a received message
Parameters
- _message: string
- _source: Box
Returns void

setReady

setReady(ready: boolean, includeChildren?: boolean): void
Sets _ready to ready. If includeChildren is true, setReady is called on each child
Parameters
- ready: boolean
- includeChildren: boolean = false
Returns void

update

update(context: object, force?: boolean): void
Update
1. Calls this.updateBegin() to initialise measurement state
2. In a loop, run measureStart() and then measureApply if possible
3. Call updateDone when finished
Parameters
- context: object
- force: boolean = false
  Force update
Returns void

`Protected` `Abstract`updateBegin

updateBegin(context: any): [MeasureState, LayoutState]
Gets initial state for a run of measurements & layout.

Called when update() is called
Parameters
- context: any
Returns [MeasureState, LayoutState]

`Protected` `Abstract`updateComplete

updateComplete(measureChanged: boolean, layoutChanged: boolean): void
Parameters
- measureChanged: boolean
- layoutChanged: boolean
Returns void